if( $expire != 1 or $expire != 2 or $expire != 3...... )

##</code><code>##

if(    $expire != int $expire
    or $expire < 1
    or $expire > 14 
) {
    die "Don't tamper with me!\n";
}

##</code><code>##

my %test;
@test{ 1 .. 14 } = ();
unless( exists $test{$expire} ) {
    die "Don't tamper with me!\n";
}